“A man who has committed a mistake and doesn't correct it, is committing another mistake.” Confucius

Confucius is conveying an idea that people should learn from their mistakes. It can be inferred that if mistakes are not corrected, then it is likely for one to repeat them.

“I find that the harder I work, the more luck I seem to have.” Thomas Jefferson

Thomas Jefferson states that luck comes with hard work. Because hard work can bring more opportunities, luck seems to follow.

“I never think of the future -- it will come soon enough.” Albert Einstein

The quote highlights the importance of the presence. Einstein is saying that future will come soon; therefore, there is no need to worry about it.